Hi
There is a mixture known as "Todo en uno" which when settled is pretty hard and can de driven over by a car with little or no disturbance. I use it for my drive. Weeds still grow through it, but then they grow through anything.
I go to Arids Filato which is about two kms from Aldea. Going towards Ampolla from Aldea it is about 100 metres past and just behind Materiales Mangrane (on your left) which is few hundred metres past the turning for Camarles on your right. The narrow road is called Cami Filato but I don't think is sign posted.
They do deliver and that is most of the cost. Delivered it costs almost as much for one ton as for ten. How much do want? Work out how many cubic meters you need and they'll tell you how many kilos it is and give you a price.
Which is nearer depends where you live. There is another near Ametller called Arids Catala
Good luck. Bricon